Dynamic Characteristics Analysis And Reliability Research On168F-O Crankshaft

Crankshaft is the core component of internal-combustion engine, its working conditions is rather harsh.When the internal-combustion engine works, the crankshaft bears complex alternating stress which will cause the fatigue failure. Due to the continuous strengthening to internal-combustion engine’s indicators, the requirement on the crankshaft’s performance is improving continually. The traditional design and research methods have been unable to meet the actual need, now widely applying CAD/CAE technology on the correlation analysis of crankshaft, and using FEM and multi-body dynamic method can analysis of crankshaft dynamic response problem better, it is the direction of strength study and reliability study of crankshaft. FEM and multi-body dynamics research on Crankshaft by the method of computer simulation, which can not only improve the design quality, but also can reduce the development cost, shorten development cycle.The subject regards the model of168F-O yacht single-throw crankshaft as the research object, on the basis of the theory analysis on crankshaft system, by using the finite element analysis software to carry out the modal analysis of the internal-combustion engine crankshaft, by using the virtual prototype simulation software to carry out the dynamic characteristics analysis of the crankshaft system; then check the static strength and fatigue strength safety factor of crankshaft; finally, combining the design theory and method of mechanical reliability to study the reliability of internal-combustion engine crankshaft. Through the above research, gets its modal shape, natural frequency and dynamic characteristic, calculates its static strength and fatigue strength safety coefficient and the reliability of the crankshaft under the maximum stress, the results indicates that the strength of the crankshaft could meet the work requirement.First of all, states the research background and significance, research purpose, method and scheme of the subject, discusses the investigation status of crankshaft at present, and analyze Kinetics and kinematics theory of the crankshaft system, then PRO-E, ANSYS and ADAMS software are introduced respectively.Then, uses PRO/E software to establish the solid model of crankshaft, then let solid model import ANSYS software, using ANSYS software to do finite element modal analysis; using PRO/E software to establish the crankshaft system physical model, and then let the crankshaft system solid model import ADAMS software, by ADAMS software to establish the crankshaft system’s dynamic model,and to do dynamics simulation analysis.Finally, uses the result of finite element analysis on the crankshaft strength safety coefficient checking, considering the factor of safety method can quantitatively reflect the reliability degree, so binding dynamics simulation analysis results and the crankshaft reliability calculation method to research crankshaft’s reliability.This paper studies the dynamic characteristics problem of the crankshaft through the CAD/CAE method,gets the natural vibration characteristics of the crankshaft and dynamic characteristics of the crankshaft system, obtains better simulation results, and by combining the theory of reliability design, verifies the internal-combustion engine crankshaft with a high reliability, it provides reference value to the engine crankshaft system design and improvement.